[8] He scored his maiden first-class century later that season against Derbyshire in an innings where all of Sussex's top four batsmen made hundreds.

[14] Following the captaincy resignation of Luke Wright midway through the 2017 season, Brown was named skipper for the remainder of the County Championship campaign.

[18] His own contribution across the season was 976 runs at an average of 51.36 including four centuries, he ended the campaign batting at number three as a specialist batsman.

In December 2021, Sussex announced that they had agreed to Brown's request to leave the club and end his contract which had two years remaining.

[21] Two weeks after his debut he made his first century for the club as he hit 157 against Kent, sharing in a stand of 273 with Liam Dawson which broke the Hampshire fifth wicket record.